Strap bending device



P 1966 D. E. MITCHELL 3,271,990

STRAP BENDING DEVICE Filed Sept. 16, 1963 DUANE E. M/ TCHELL hi 5) HA5 ATTORNEYS HAzQ/s, K/EcH, RUSSELL 3: KER/V United States Patent 3,271,990 STRAP BENDING DEVICE Duane E. Mitchell, Shandon Rte., Paso Robles, Calif. Filed Sept. 16, 1963, Ser. No. 309,201 3 Claims. (Cl. 72389) The present invention relates in general to a device for bending straps to form such things as pipe or tubing hangers or clamps, or the like.

A primary object of the invention is to provide a very simple and inexpensive strap bending device designed to be actuated by the jaws of an ordinary vise.

Such a strap bending device finds particular utility in home work shops and in small machine shops, although its usefulness is not limited thereto.

More particularly, the present invention comprises a strap bending device which includes: a base; two spaced primary dies mounted on the base; a secondary die movably mounted on the base for movement toward and away from the primary dies along a die path which is perpen dicular to a line extending between the primary dies and which lies midway between the primary dies; the primary dies being engageable with one side of a strap at spaced primary points and the secondary die being engageable with the other side of the strap at a secondary point midway between the primary points; and the primary dies being engageable by one jaw of a vise and the secondary die being engageable by the other jaw thereof to produce movement of the secondary die toward the primary dies, upon closing movement of the jaws of the vise, to bend the strap around the primary and secondary dies.

Another object of the invention is to provide a strap bending device of the foregoing character wherein the primary dies are adjustably mounted on the base for movement toward and away from each other along a primary die path which is perpendicular to and bisected by the path of movement of the secondary die, and wherein locking means are provided for locking the primary dies relative to the base in predetermined positions on the primary die path. Making the primary dies adjustable as to position in this manner permits the use of primary and/or secondary dies of various diameters and permits the use of the device with straps of various thicknesses, which is an important feature.

Still more specifically, an important object of the invention is to provide a simple and inexpensive strap, bending device, capable of actuation by a vise, which includes: a flat base; two spaced, aligned, primary die slots in the base; two primary die means respectively movable along the primary die slots; means for locking the primary die means relative to the base in predetermined positions along the primary die slots; a secondary die slot in the base perpendicular to and extending between the primary die slots; a secondary die means movable along the secondary die slot; the primary die means respectively including primary dies engageable with one side of a strap at spaced primary points and the secondary die means including a secondary die engageable with the other side of the strap at a secondary point midway between the primary points; and the primary dies being engageable by one jaw of a vise and the secondary die being engageable by the other jaw thereof to produce movement of the secondary die toward the primary die path, upon closing movement of the jaws, to bend the strap around the primary and secondary dies.

Another and important object of the invention is to provide a plurality of sets of primary and secondary dies capable of being used interchangeably, the dies of the various sets having cylindrical surfaces of various diameters to form such things as pipe or tubing clamps or hangers of various sizes.

Another object of the invention is to provide sets of primary and secondary dies all having cylindrical surfaces of same diameter.

Still another object is to provide sets of dies wherein the diameter of the cylindrical surface of the secondary die exceeds the diameters of the cylindrical surfaces of the primary dies.

With the foregoing different die sets, the bends formed in a strap may all have the same diameter, or they may different diameters, depending upon the intended use of the strap.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the strap bending art in the light of this disclosure, may be achieved with the exemplary embodiments of the invention described in detail hereinafter and illustrated in the accompanying drawing, in which:

FIG. 1 is a side elevational view on a reduced scale showing the strap bending device of the invention in its operating position in a vise;

FIG. 2 is an enlarged top plan view showing the strap bending device in its operating position in a vise;

FIG. 3 is a further enlarged, bottom plan view showing in position in the device a strap which is tobe bent;

FIG. 4 is a view similar to FIG. 3, but showing the strap after bending;

FIG. 5 is a still further enlarged, fragmentary sectional view taken along the irregular arrowed line 5-5 of FIG. 4;

FIG. 6 is a view similar to FIG. 4, but showing another embodiment of the invention; and

FIG. 7 is a view also similar to FIG. 4, but showing still another embodiment of the invention.

Referring initially to FIGS. 1 to 5 of the drawing, the strap bending device of the invention is designated generally therein by the numeral 10 and includes a base 12 having the form of a flat plate. As shown in FIGS. 1 and 2, the underside of the base 12 is adapted to rest on jaws 14 and 16 of a vise 18 when the device 10 is in its operating position.

The base 12 is provided therein with two spaced, aligned, primary-die guide slots 20 in which two primary die means 22 are movable along a primary die path formed by the guide slots 20. The base 12 is also provided with a secondary-die guide slot 24 perpendicular to the primary die path and bisecting and extending into the space between the primary-die guide slots 20. A secondary die means 26 is movable relative to the base 12 along the secondary-die guide slot 24.

Each primary die means 22 is shown as including a tubular, cylindrical, primary die 28. Each primary die means 22 also includes a bolt 30 which extends through the corresponding primary die 28 and the corresponding guide slot 20 and which is secured by a nut 32. By tightening the nuts 32, the primary dies 28 may be locked in adjusted positions in the guide slots 20 with a predetermined spacing between the primary dies, as will be discussed in more detail hereinafter.

The secondary die means 26 similarly includes a tubular, cylindrical secondary die 34, and includes a bolt 36 which extends through the secondary die and the secondary-die guide slot 24 and which is secured by a nut 38. In use, the nut 38 is not tightened sufliciently to lock the secondary die 34, wherefore it is free to move along the secondary-die guide slot 24 when the strap bending device 10 is placed in the vise 18 and the jaws 14 and 16 of the latter are closed.

Referring to FIG. 3 of the drawing, a strap 40 to be bent is shown as inserted between the primary dies 28 and the secondary die 34 so that the primary dies engage one side of the strap at spaced primary points and so that the secondary die engages the other side of the strap at a secondary point midway between the primary points. The positions of the primary dies 28 in the primary-die guide slots 20 are so adjusted as to provide the desired final configuration for the strap 48, the primary dies 28 preferably being locked in their adjusted positions by tightening the nuts 32. In FIG. 3 of the drawing, the primary dies 28 are shown locked in positions to produce the particular final strap configuration shown in FIG. 4, wherein the strap is bent to radii such as to permit it to act as a hanger for holding a pipe, tubing, or the like, flat against a supporting surface, not shown, to which the hanger is attached. It will be apparent that the positions of the primary dies 28 may be adjusted to provide various angular extents for the bends in the strap produced thereby, depending upon the desired final configuration for the resulting hanger, and to accommodate various strap thick nesses.

In use, the device is placed in the vise 18, as shown in FIGS. 1 and 2, with the strap 40 in the proper position between the primary dies 28 and the secondary die 34. Then, the jaws 14 and 16 of the vise 18 are closed. This displaces the secondary die 34 toward and between the primary dies 28, as shown in FIG. 4 of the drawing, closing movement of the vise jaws 14 and 16 being limited by engagement of the jaw 16 with the ends of the strap 40. The result is the strap configuration shown in FIG. 4 of the drawing, which configuration is such as to permit the bent strap to be used as a hanger for holding a pipe or tubing against a fiat surface.

Either before or after the strap 40 has been bent into its desired final configuration, the ends thereof may be provided with holes, not shown, to receive screws, nails, or the like, for securing it, and a pipe or tube supported thereby, in place.

Referring to FIG. 6 of the drawing, illustrated therein is a strap 50 bent to a configuration to act as a hanger for a larger-diameter pipe or tube by substituting largerdiameter primary dies 52 and a correspondingly largerdiameter secondary die 54 for the primary dies 28 and the secondary die 34, respectively. As will be apparent, various other die sets, not shown, comprising primary and secondary dies of various other diameters, may be provided so that straps capable of securing pipes or tubes of a wide range of diameters may be bent.

In FIGS. 1 to 6 of the drawing, the primary and secondary dies of each set are shown as having the same diameter. However, this is not necessary since the secondary die may have a diameter larger or smaller than the diameters of the primary dies. However, the diameters of the primary dies are preferably the same in each instance. In any event, the diameter of the secondary die is such'that it may be displaced between the primary dies far enough to bend the middle of the strap sufficiently to receive a pipe or tube entirely within the resulting concavity. This will be clear from FIGS. 4 and 6, for example.

Referring to FIG. 7 of the drawing, an alternative is to bend the middle of the strap only enough to receive half of a pipe or tube in the resulting concavity, Wherefore two straps are used together to act as a pipe or tubing clamp for receiving the entire pipe or tube therebetween. In this case, cylindrical primary dies 62 are used in conjunction with a hemicyliudrical secondary die 64 to provide a bent strap 66 having a configuration such as to receive half of a pipe or tube therebetween. The bent strap 66 is designed to be used in conjunction with a similar strap 68, shown in broken lines, which is reversed in position relative to the strap 66 to form between the two straps an opening of a size to receive a pipe or tube having a radius corresponding to the radii of the bent intermediate portions of the straps 66 and 68.

Another way of expressing the foregoing is that each strap 66 and 68 is provided with a hemicylindrical concavity therein. This is effected by the use of the hemicylindrical secondary die 64. As will be apparent, when the primary and secondary dies 62 and 64, with an unbent strap therebetween, are placed in the vise 18 and the jaws 14 and 16 are closed, one of the jaws will engage the fiat side of the hemicylindrical secondary die 64 and the ends of the bent strap to so limit the bending of the strap as to form it with a hemicylindrical concavity. Thus, by using a hemicylindrical secondary die, a generally hemicylindrical concavity will result. On the other hand, by using a cylindrical secondary die, a cavity large enough to receive a cylindrical object will result.

Thus, the strap bending device of the invention is quite versatile and may be used to provide tubing or pipe clamps of different types.

Although exemplary embodiments of the invention have been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated therein without departing from the spirit of the invention as defined by the claims which follow.

I claim:

1. In a strap bending device for use in a vise, the combination of:

(a) a fiat base having a lower surface seatable on the jaws of the vise;

(b) two spaced primary dies depending below said lower surface of said base and adjustably mounted on said base for movement toward and away from each other along a primary die path extending therebetween;

(c) a secondary die depending below said lower surface of said base and movably mounted on said base for movement toward and away from said primary die path along a secondary die path perpendicular to said primary die path and lying between said primary dies;

(d) said primary dies being engageable with one side of a strap at spaced primary points and said secondary die being engageable with the other side of the strap at a secondary point between said primary points; and

(e) said primary dies being engageable by one jaw of the vise and said secondary die being engageable by the other jaw thereof to produce movement of said secondary die toward said primary die path, upon closing movement of said jaws, to bend said strap around said primary and secondary dies.

2. In a strap bending device for use in a vise, the

combination of:

(a) a fiat base having a lower surface seatable on the jaws of the vise;

(b) two spaced primary dies depending below said lower surface of said base and adjustably mounted on said base for movement toward and away from each other along a primary die path extending therebetween;

(c) means for locking said primary dies relative to said base in predetermined positions on said primary die path;

(d) a secondary die depending below said lower surface of said base and movably mounted on said base for movement toward and away from said primary die path along a secondary die path perpendicular to said primary die path and lying between said primary dies;

(e) said primary dies being engageable with one side of a strap at spaced primary points and said secondary die being engageable with the other side of the strap at a secondary point between said primary points; and

(f) said primary dies being engageable by one jaw of the vise and said secondary die being engageable by the other jaw thereof to produce movement of said secondary die toward said primary dies path, upon closing movement of said jaws, to bend said strap around said primary and secondary dies.

3. In a strap bending device for use in a vise, the combination of:

(a) a flat base having a lower surface seatable on the jaws of the vise;

(b) two spaced, aligned, primary die slots in said base;

(c) two primary die means depending below said lower surface of said base and respectively movable along said primary die slots;

(d) means for locking said primary die means relative to said base in predetermined positions along said primary die slots;

(e) a secondary die slot in said base perpendicular to and extending between said primary die slots;

(f) a secondary die means depending below said lower surface of said base and movable along said secondary die slot;

g) said primary die means respectively including primary dies engageable with one side of a strap at spaced primary points and said secondary die means including a secondary die engageable with the other side of the strap at a secondary point midway between said primary points; and

(h) said primary dies being engageable by one jaw of the vise and said secondary die being engageable by the other jaw thereof to produce movement of said secondary die toward said primary die path, upon closing movement of said jaws, to bend said strap around said primary and secondary dies.

References Cited by the Examiner UNITED STATES PATENTS CHARLES W. LANHAM, Primary Examiner.

L. A. LARSON, Assistant Examiner. 

1. IN A STRAP BENDING DEVICE FOR USE IN A VISE, THE COMBINATION OF: (A) A FLAT BASE HAVING A LOWER SURFACE SEATABLE ON THE JAWS OF THE VISE; (B) TWO SPACED PRIMARY DIES DEPENDING BELOW SAID LOWER SURFACE OF SAID BASE AND ADJUSTABLY MOUNTED ON SAID BASE FOR MOVEMENT TOWARD AND AWAY FROM EACH OTHER ALONG A PRIMARY DIE PATH EXTENDING THEREBETWEEN; (C) A SECONDARY DIE DEPENDING BELOW SAID LOWER SURFACE OF SAID BASE AND MOVABLY MOUNTED ON SAID BASE FOR MOVEMENT TOWARD AND AWAY FROM SAID PRIMARY DIE PATH ALONG A SECONDARY DIE PATH PERPENDICULAR TO SAID PRIMARY DIE PATH AND LYING BETWEEN SAID PRIMARY DIES; (D) SAID PRIMARY DIES BEING ENGAGEABLE WITH ONE SIDE OF A STRAP AT SPACED PRIMARY POINTS AND SAID SECONDARY DIE BEING ENGAGEABLE WITH THE OTHER SIDE OF THE STRAP AT A SECONDARY POINT BETWEEN SAID PRIMARY POINTS; AND (E) SAID PRIMARY DIES BEING ENGAGEABLE BY ONE JAW OF THE VISE AND SAID SECONDARY DIE BEING ENGAGEABLE BY THE OTHER JAW THEREOF TO PRODUCE MOVEMENT OF SAID SECONDARY DIE TOWARD SAID PRIMARY DIE PATH, UPON CLOSING MOVEMENT OF SAID JAWS, TO BEND SAID STRAP AROUND SAID PRIMARY AND SECONDARY DIES. 